Doruneh is an active left- lateral strike- slip fault in North-East Iran. Surface trace of this fault is about 700 km long, and cuts across Quaternary and Tertiary deposits. In some places along the fault, sediments of Paleogene. Neogene, and alluvial fans of Quaternary age are displaced by the fault. Left- lateral displacement between 91-457 m are evident in Landsat images between east of Beiragh and east of Khalil-abad. Displacements are also evident in streams that are incised over the above mentioned deposits. We have tried to estimate the recent history of activity on the fault on the basis of the measured displacements and estimated slip rates of the fault. Estimated age of left- lateral movement inception on the fault is very much younger than the displaced geologic units. These observations indicate that Doruneh Fault has been mostly active during the last few millions, which in turn proves the fault to be an active structure.